Transmitter for telephones



(No Model.)

4 JYA. BROWN.- TRANSMITTER FOR TELEPHONBS.

No. 601,610. Patented July 18, 1893.

moewfoz UNITED STATE PATENT OFFICE.

JAMES A. BROWN, OF MOLINE, ILLINOIS.

TRANSMITTER FOR TELEPHONES.

SPECIFICATION forming part of Letters Patent No. 501,610, dated July 18, 1893. Application filed April 26, 1893. Serial No. 471,917. (No model.)

.To all whom it may concern.-

Be it known that I, JAMES A. BROWN, a citizen of the United States, residing at Moline, in the county of RockIsland and State of Illinois, have invented certain new and useful Improvements in Transmitters for Telephones; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to certain new and useful improvements in transmitters for electrical telephones for transmitting articulate speech, and it has for its objects to produce an undulating current for practical telephonic service, by vibrating armature or armatures within a magnetic field, the armatures being carried by a movable or pivoted lever, and connections beinginterposed between the diaphragm and the lever thus carrying the armatures, whereby the vibrations of the diaphragm will be communicated to the armatures through the medium of the lever and its connections and the scope of the vibrations will be greatly increased, thus cutting a greater number of lines of force within the magnetic field, and thereby producing an undulating current of greater volume and varying intensity.

A further object of the invention is to provide a transmitter in which the diaphragm is removed from the magnetic field, thereby permitting the use of a non inductive material in the construction of the diaphragm, such, for instance, as mica, which is much more sensitive to acoustic action than the metallic diaphragms heretofore used.

To these ends and to such others as the invention may pertain, the same consists in the peculiar construction and in the novel combinatiomarrangement and adaptation of parts all as more fully hereinafter described, shown in the accompanying drawings and then specifically defined in the appended claims.

The invention is fully illustrated in the accompanying drawings, which with the letters of reference marked thereon form a part of the diaphragm is provided upon one of its sides with an extension D to which is secured the metallic frame E, which carries a magnet E either electro or permanent. This magnet is provided with a screw threaded opening, for the reception of a screw E, by means of which it may be adjusted horizontally, as shown. Upon the opposite side of the diaphragm is similarly mounted a magnet, which magnet is mounted upon a screw, F passed through an extension D of the ring D.

The armatures E and F of the magnets E and F respectively are carried by the free ends of a lever G, which lever is pivoted at its longitudinal center to the forwardly extending arm H, of the frame or bracket E.

In order to insure the armatures remaining at all times within the magnetic field, a stop I is employed. It will be understood that when in use the stop is at all times free from contact with the end of the lever carrying the armatures, and the office of the stop I, is merely to prevent the end of the said lever from falling out of the magnetic field when the instrument is out of use or in case of accident.

To the rear face of the diaphragm is secured a lug or block J, having a concave aperture J, within which is seated one of the conical ends of a bar or rod K. The opposite end of said rod which is also of conical form, is similarly seated in a concave recess L in the lug or extension L, upon theface of the lever G. Said lug L is formed integral with the said lever.

The operation of the device will be readily understood; the diaphragm being set in vibration by acoustic action, transmits its action to the lever G, at the point of connection there with of the rod K. The said point at which the rod K, connects with the lever being at one side of the pivoted point of the lever, the action thus imparted thereto will serve to move the lever upon its pivot, thus imparting to the free ends of the lever upon which the armatures are mounted, a movement which While corresponding precisely with the pulsations of the diaphragm, will be much greater in scope or on the distance traversed, thereby cutting a much greater number of lines of magnetic force in the magnetic field than would be secured with the movement of the armature if limited to the movements of the diaphragm, and thus vary to a greater degree the intensity or force of the current, as will be understood by those skilled in theart.

Having thus described my invention, what I claim to be new, and desire to secure by Letters Patent, is-- 1. In combination with the diaphragm of a telephone transmitter, adapted forusein teleresence of two witnesses.

phones, said diaphragm being placed out of the ma netic-field se arated ma nets in circuit, armatures for said magnets, and conneci tions between said armatures and the diaphragm located between the magnets and adapted to impart to the armatures the vibrations of the diaphragm and to increase the scope and amplitude of said vibrations, substantially as described and for the purpose specified.

2. A transmitter for telephones comprising a diaphragm located between two magnets and placed outside of the magnetic field, and connected with an armature common to two magnets in circuit, substantially as described.

3. In a transmitter for use in electric and magnetic telephones, a diaphragm placed outside of the magnetic field, two or more magnets in circuit, armatures for said magnets carried upon a pivoted lever, connections between said diaphragm and the lever carrying the armatures at one side of the pivotal point of the lever, whereby the vibrations of the diaphragm are communicated to the armatures and increased in scope and amplitude, substantially as described.

In testimony whereof I aflix my sign aturc in JAMES A. BROWN.

Witnesses:

FRANKLIN H. HOUGH, E. S. TRULL. 

